Joseph s



J. S. LOSEE AND F- ,A. HOWARD.

' MIXTURE HEATER.

APPLICATION HLED AUG.28,19I8.

1 3 1 5, 73 0 Patented Sept. 9, 1919.

UNITED STATES PATENT oFFicE.

JOSEPH S. LGSEE, 0F HEBRON, AND FRANK A. HOWARD, OF CHICAGO, ILLINOIS; SAID HOWARD ASSIGNOR T0 SAID LOSEE.

MIXTURE-HEATER.

Application filed August 28, 1918.

To all whom it may concern:

Be it known that we, JOSEPH S. Loser. and FRANK A. HOWARD, citizens of the United States, residing at Hebron, in the county of McHenryand State of Illinois, and Chicago, in the county of Cook and State of Illinois, respectively, have invented new and useful Improvements in Mixture-l-leaters, of which the following is a specification.

Our invention relates to improvements in mixture heaters for internal combustion engines and will be fully understood from the following specification, taken in connection with the. accompanying drawing, in WlliCll-- Figure 1 is a side elevation of a mixture heater constructed in accordance with the invention, the casing of the heater being shown in longitudinal section; Fig. 2 is a longitudinal section through the heater and easing, the elbows being removed; and Fig. 3 is a section on the line 3 of Fig. 2.

In the design of the present mixture heater we have proceeded upon the theory that for the handling of mixtures of rela tively heavy hydrocarbon fuels, such as present day motor gasolene,the most satisfactory results will be obtained by supplying the heat directly to the unvaporized fuel particles in the mixture. We have found by test that even where. the air for carburation is at such a temperature, as to insure complete vaporization of the liquid fuel in time, this result is not in fact accomplished within the carbureter or intake conduits of the ordinary internal combustion engine, for

two reasons, 2'. 6., the liquid fuel is not reduced to a fine enough state of subdivision by the action of the spray nozzle of the carbureter, and the transfer of heat from the air to the fuel particles is not sufliciently rapid to complete their vaporization in the length of time in which the fuel traverses the intake conduit and enters the engine cylinder. It is of course true that there is a continued-vaporizing action during the inlet and compression strokes of the piston in the engine cylinder and in some cases this additional time element may be suflicient to permit the complete vaporization of the bulk of the fuel but it is necessarily true that a certain proportion of the unvaporized fuel which enters the cylinder is deposited upon the lubricated walls thereof, dilutin the film of lubricant on the walls and by a 11113 Specification of Letters Patent.

Patented Sept. 9, 1919.

Serial No. 251,794.

tension so reduced that vaporization proceeds very slowly. Thedemonstrated result .of this phenomenon is the accumulation within the crank-case of the engines of the heavier fractions of the liquid fuel, this accumulation being in many cases more rapid than the loss of lubricant, so that the oil reservoir or circulating system will in fact appear to be manufacturing lubricating oil instead of consuming it.

We have found-that it is readily possible without altering the general design of the engine or carburetor, or changing the character of fuel. to overcome all of these disadvantages. The remedy for the situation which is represented by the present invention does not reside primarily in raising the temperature of the air or of the mixture but rather in applying a small quantity of heat efliciently in such manner that it shall exert its main effect in making up the loss of latent heat of vaporization of the fuel. This result is in general attained by the use of an element inserted in the mixture passage and so designed as to act as a separator for throwing out of the mixture stream the suspended, unvapori'zed fuel particles therein, and causing these particles to impinge upon metallic surfaces which are maintained at a moderately high temperature.

It has been our special purpose to provide a device capable of' efficiently performing these functions without causing any appreciable loss in volumetric efficiency of the motor either by unduly heating and thus expanding the mixture, or by imposing such resistance to its flow as to give a perceptlble drop in density. i

The mixture heater in accordance with the present invention, which is illustrated by the accompanying drawing, is in the form of' a casting having flanges 10 and 11 at its end for attachment to the mating flanges of the carbureter and intake manifold of the engine. Between these flanges the body p tion of the casting is expanded laterally to an internal diameter approximately tunes the bore of the intake passage. In the con struction shown, this expanded portion of the heater is not symmetrically arranged with; respect to the flanges, being offset toward one flange. s h hb th broken section-line 3, 3 on Fig. 2. By virtue of this 2, there is not sufficient space behind thev flange 11 for a nut, and this flange must therefore be secured by a cap-screw entering a threaded aperture 13, or by a stud set in this aperture. By this construction,

which permits of the use of a nut back of the flange for securing the device on one end and of a stud or cap-screw. on the other, in combination with an internal construction which is symmetrical with respect to the two ends, as will later be described, it is possible to apply the mixture heater between the carbureter and manifold, or between the carbureter and the engine casting where no separate manifold is employed, regardless of Y Y the type of flange-securing means used in 'tions therefor are secured.

any particular instance.

The entire exterior surface of the expanded portion ofthe body casting is checkered or otherwise roughened, as shown at 14, to provide a maximum surface for contact with the heating gases. Halfway between the flanges 10'and 11, and therefore somewhat offset from the center of the expanded section, there is a flange 15, the purpose of which is to provide sufficient depth of metal to permit of drilling and tapping at any point around the circumference of the heater, for the fastening of the screws 16 (Fig. 1) by which the jacket-casing and elbow connec- This jacket-casing 17, which may be formed either of one piece or of two pieces of smooth sheet-metal, is preferably expanded in the center, as illustrated, and has truly cylindrical end portions which rest ingrooves 18 in the inner edges of the flanges 10 and 11. The jacketcasing is perforated at diametrically oppo' site points and formed to receive the ends of a pair of flattened elbows 19 by which the heating gas is circulated through the jacket.

Mounted centrally Within the expanded body portion of the casting there is a de-. flector member 20, which is-circular in all cross-sections and symmetrical with respect to its-transverse central sectional plane. Be- 7 tween the outer surface of the deflector member 20 and the inner surface of the expanded body casting there are arranged four generally helicoidal ribs designated 21, these ribs representing helices of very long pitch,

for example, a pitch four times the length of the deflector 20. The helicoidal. ribs 21 are also'preferably of decreasing thickness from the center toward their ends, as shown in Fig. 2. Both the inner surface of the expanded body portion and the outer surface of the deflector 20 are preferably grooved or corrugated, the corrugations be- I ing on helical lines parallel with the ribs 21. This construction very much increasesthe effective area of the. surfaces and is believed to have an additional beneficial ef-' feet, which will be later pointed out. We hare-found that-the entire mixture heater, that is, the body portion, the deflector and they ribs, may be conveniently made as an integral casting, it being possible, likewise, to cast the jacket-cover 17 as an integral partof the heater. We do not recommend this latter'construction, however, except in special instances.

As will be seen from Fig. 2, the depth OI thickness of the four helicoidal passages outlined by the ribs 21, deflector 20 and inner surface of the body, decreases as the passages approach the maximum diameter of the deflector, the effect being to preserve a mixture passage of substantially uniform cross-sectional .area throughout. We have even found it possible to slightly decrease the cross-sectional area of the mixture passages as represented by the section shown in Fig. 3 without a sensible loss of head of the mixture, the contraction and expansion being so gradual that the Venturi-tube principle applies in a measure. This is highly advantageous, since the separating action, asthe result of which the unvaporized fuel particles are thrown against the heated surfaces, increases with the velocity.

In the operation of our mixture heater the same is inserted as a part of the inlet passage of the engine, preferably by attachment between the mating flanges of the carbureter and manifold, as described. One of the elbows 19 is connected withv the watercirculation system or the exhaust pipe of the engine, preferably the latter, since with the,

heavier grades of fuels now available the temperature of the circulating water is -hardly suflicient to effect complete vaporizais divided into four helicoidal streams by the ribs 21. It will be noted that the path of the gases in these helicoidal passages is such that centrifugalv force is brought into play to the maximum extent with a minimum change in direction of the gases, or more accurately, with a minimum resistance to flow. The helicoidal twist of the ribs 21 of course tends to throw out of the mixture stream the unvaporiz'ed fuel particles .thereof "against the surfaces of these ribs,

while the outward and inward curvature of" each passage following the walls of the dcflector 20 brings the action of centrifugal force into play in a plane at right angles to the force brought into play by the helicoidal twist. As the result of this double curvature of each of the four mixture passages the entrained fuel particles are effectively separated from the mixture stream, and furthermore, such separation is not effected at a single point or on a small surface but takes place throughout the length and over all of the surfaces of the heater, wetting all of these surfaces and forming a film thereon which is subjected to the direct heating effect of the exhaust gases transferred through the metal walls. Undersuch cond-itions thefilm is vaporized as it is deposited, with the result that the mixture issuing from the heater contains the same proportions of fuel and air as that entering the heater, the sole difference being that the entering stream carries the fuel largely in the form of unvaporiz'ed liquid droplets, while the issuing stream carries the fuel almost entirely in the form of vapor or at least in atoms or droplets which areso small as to approach the vesicular condition and remain permanently in suspension. We find that the mixture heater design illustrated does not depend for its efficiency solely upon the supply of heat to the fuel but acts likewise as an eflicient mechanical device for breaking up the larger fuel particles and preventing the irregularities of motor action which result from the formation of slugs of liquid fuel.

The particular design of mixture heater herein described is especially desirable for attachment to existing motors, in that it is of such small length as to be capable of insertion between the carbureter and manifold or cylinder-block in almost all cases. The mixture passage or multiple of passages within the short length of the heater. is nevertheless of such design that it is capable of efliciently performing its functions and that without imposing any appreciable resistance to the flow of the mixture or materially heating and thus expanding the mixture and causing loss of volumetric efficiency of the motor, an objection which has heretofore been common to practically all mixture heater designs in which the heat supply was sufficient to thoroughly dry the mixture. We believe that the successful operation of the present design is primarily due to the fact that all of the surfaces therein are arranged to give up heat rather to the unvaporized fuel particles than to the air.

While we have in the foregoing described in considerable detail a preferred embodiv ment of our invention, together with our theories as to the manner in which thesame operates, it will be understood that this is illustrative only, for the purpose of making the invention more clear and that the id vention is not to be regarded as limited to the details described nor as dependent upbn the soundness or accuracy of the theories gitudinal section supported centrally within said hollow member and forming therewith an annular mixture passage which decreases in thickness from the ends toward the center, means for supplying heating fluid to the jacket of said member, and means for supplying heat by conduction from the said member to, the deflector.

I 2. A mixture heater forming a part of the intake passage of an internal combustion engine and comprising a jacketed hollow member of circular cross-section continuously increasing in diameter from its ends to its central'section, a double conical deflector supported centrally Within said hollow member and forming therewith an annular mixture passage, a plurality of ribs disposed longitudinally of the passage and joining the said deflector and body to subdivide the annular passage, and means for supplying heating fluid to the jacket of the said member.

3. A mixture heater forming a part of the intake passage of an internal combustion engine and comprising a jacketed body portion having a mixture passage therein continuously mcreasing in diameter from its endstoward its central section, a deflector centrally mounted within the passage and of gradually increasing diameter from its ends toward its central section, a plurality of generally helicoidal ribs joinin the deflector and the body, and means or supply ing heating fluid to the jacket of the said body.

4. A mixture heater comprising an integral casting including end flanges, a hollow body portion of circular cross-section and of a diameter continuously increasing from the flanges toward the center, a deflector centrally mounted within the body portion and of similar section to form an annular mixture passage, and a plurality of longitudinal ribs joining the deflector and body portion and subdividing the said passage longitudinally, in combination with a separable sleeve esting on the said flanges and forming wit the latter a jacket space for heating fluid.

5. A mixture heater comprising an integral casting,'inc1uding end flanges, a ho llow body portion of circular cross-section trally expanded body portion of circular cross-section and circular securing flanges formed integrally with'the ends of said body portion; one of said flangesonly being spaced-from the central expanded portion by a'distance sufiicient to permit of the ap plication of ,a securing nut on the inner face of the flange, and a separable sleeve resting on the peripheries of the said flanges to form an annular jacket chamber Within which the securing nuts are located.

7. A mixture heater designed for attachment to an internal combustion engine to form a part of an intake passage thereof and comprising an integral body having endsecuring flanges of circular cross-section in combination with a detachable jacket casing fitted to the peripheries of the said. flanges and fittings carried by the said casing for the attachment of fluid-inlet and outlet pipes, whereby the casing may be angularly adjusted with reference to the integral body anal removed therefrom without altering the b0 y. v g

8. A mixture heater for internal combustion engines and adapted to form a part of the mixture passage of such engines and comprising means forming a plurality of separated mixture passages each curving. outwardly and then inwardly and helically around the projected axis ofthe mixture passage, the aggregate area of all of said passages throughout their lengths being substantially equal to the area of the mixture passage, and means for heating the surfaces bounding the said mixture passages.-

9. A mixture heater forming a part of the intake passage of an internal combustion engine and comprising a jacketed body portion having a mixture passage therein,

a plurality of generally helicoidal ribs projecting radially into the mixture passage,

helicoidal corrugations generally parallel with the said ribs and formed in the surface of the mixture passage; and means for supplying heating fluid to the jacket of the said body,

aosEPH s. Loses, Y shaman. HOWARD. 

